Figure 8D-2. Example of Location Plan for Flashing-Light Signals and Four-Quadrant Gates
This figure illustrates three examples of railroad tracks crossing roadways with four-quadrant gates and signals.
A note states: "In an effort to simplify the figure to show typical location plans for flashing-light signals and four-quadrant gates, not all traffic control devices are shown on this figure." A legend shows a black arrow indicating the direction of travel on the roadway.
The first example shows two railroad tracks crossing a two-lane roadway at an obtuse angle, with the tracks shown running from the southwest on the left to the northeast on the right. Arrows show the direction of travel on the roadway is one lane in each direction. On each side of the railroad tracks, two gates are shown: one that extends across the entire right lane (the approach lane) and one that extends across the entire left lane (the exit lane). On each side of the railroad tracks, a median island is shown placed between the two gates as determined by an engineering study. On each side of the tracks, the dimensioned distance from the center line of the near track to the gate across the right (approach) lane is shown as 3.0 m (10 ft) MIN. The dimensioned distance from the center line of the far track to the exit gate in the right lane is shown as 3.7 m (12 ft) MIN.
The second example shows the same example of railroad tracks crossing a roadway as the first example, except these tracks are shown at an acute angle, with the tracks shown running from the northwest on the left to the southeast on the right.
The third example shows a railroad track crossing a two-lane roadway at a right angle. Arrows show the direction of travel is one lane in each direction. On each side of the railroad tracks, two gates are shown: one that extends across the entire right (approach) lane and one that extends across the entire left (exit) lane. On each side of the tracks, the dimensioned distance from the center line of the near track to each gate is shown as 3.7 m (12 ft) MIN.
A note states "Lateral clearances shall be in accordance with Figure 8D-1 and Chapter 8D."
